diff --git a/shell/platform/tizen/flutter_tizen_engine_unittest.cc b/shell/platform/tizen/flutter_tizen_engine_unittest.cc
index 2ffd863c03a10..dc7bb1d5b68b2 100644
--- a/shell/platform/tizen/flutter_tizen_engine_unittest.cc
+++ b/shell/platform/tizen/flutter_tizen_engine_unittest.cc
@@ -143,5 +143,88 @@ TEST_F(FlutterTizenEngineTest, RunDoesExpectedInitialization) {
   modifier.embedder_api().Shutdown = [](auto engine) { return kSuccess; };
 }
 
+TEST_F(FlutterTizenEngineTest, SendPlatformMessageWithoutResponse) {
+  EngineModifier modifier(engine_);
+
+  const char* channel = "test";
+  const std::vector<uint8_t> test_message = {1, 2, 3, 4};
+
+  // Without a response, SendPlatformMessage should be a simple pass-through.
+  bool called = false;
+  modifier.embedder_api().SendPlatformMessage = MOCK_ENGINE_PROC(
+      SendPlatformMessage, ([&called, test_message](auto engine, auto message) {
+        called = true;
+        EXPECT_STREQ(message->channel, "test");
+        EXPECT_EQ(message->message_size, test_message.size());
+        EXPECT_EQ(memcmp(message->message, test_message.data(),
+                         message->message_size),
+                  0);
+        EXPECT_EQ(message->response_handle, nullptr);
+        return kSuccess;
+      }));
+
+  engine_->SendPlatformMessage(channel, test_message.data(),
+                               test_message.size(), nullptr, nullptr);
+  EXPECT_TRUE(called);
+}
+
+TEST_F(FlutterTizenEngineTest, SendPlatformMessageWithResponse) {
+  EngineModifier modifier(engine_);
+
+  const char* channel = "test";
+  const std::vector<uint8_t> test_message = {1, 2, 3, 4};
+  auto* dummy_response_handle =
+      reinterpret_cast<FlutterPlatformMessageResponseHandle*>(5);
+  const FlutterDesktopBinaryReply reply_handler = [](auto... args) {};
+  void* reply_user_data = reinterpret_cast<void*>(6);
+
+  // When a response is requested, a handle should be created, passed as part
+  // of the message, and then released.
+  bool create_response_handle_called = false;
+  modifier.embedder_api().PlatformMessageCreateResponseHandle =
+      MOCK_ENGINE_PROC(
+          PlatformMessageCreateResponseHandle,
+          ([&create_response_handle_called, &reply_handler, reply_user_data,
+            dummy_response_handle](auto engine, auto reply, auto user_data,
+                                   auto response_handle) {
+            create_response_handle_called = true;
+            EXPECT_EQ(reply, reply_handler);
+            EXPECT_EQ(user_data, reply_user_data);
+            EXPECT_NE(response_handle, nullptr);
+            *response_handle = dummy_response_handle;
+            return kSuccess;
+          }));
+  bool release_response_handle_called = false;
+  modifier.embedder_api().PlatformMessageReleaseResponseHandle =
+      MOCK_ENGINE_PROC(
+          PlatformMessageReleaseResponseHandle,
+          ([&release_response_handle_called, dummy_response_handle](
+               auto engine, auto response_handle) {
+            release_response_handle_called = true;
+            EXPECT_EQ(response_handle, dummy_response_handle);
+            return kSuccess;
+          }));
+  bool send_message_called = false;
+  modifier.embedder_api().SendPlatformMessage = MOCK_ENGINE_PROC(
+      SendPlatformMessage, ([&send_message_called, test_message,
+                             dummy_response_handle](auto engine, auto message) {
+        send_message_called = true;
+        EXPECT_STREQ(message->channel, "test");
+        EXPECT_EQ(message->message_size, test_message.size());
+        EXPECT_EQ(memcmp(message->message, test_message.data(),
+                         message->message_size),
+                  0);
+        EXPECT_EQ(message->response_handle, dummy_response_handle);
+        return kSuccess;
+      }));
+
+  engine_->SendPlatformMessage(channel, test_message.data(),
+                               test_message.size(), reply_handler,
+                               reply_user_data);
+  EXPECT_TRUE(create_response_handle_called);
+  EXPECT_TRUE(release_response_handle_called);
+  EXPECT_TRUE(send_message_called);
+}
+
 }  // namespace testing
 }  // namespace flutter